Field of the Invention
The present invention relates to a technical field of monitoring an abnormality in a transport container in an apparatus that processes substrates having been carried into the apparatus with the use of the transport container.
Description of Related Art
In a semiconductor manufacturing factory, semiconductor substrates are contained in a transport container, and the transport container is transported to a semiconductor manufacturing apparatus by an automatic guided vehicle (AGV) or an overhead hoist transporter (OHT). The semiconductor manufacturing apparatus includes a carry-in and carry-out port for the transport container, and a processing block that processes semiconductor substrates. A sealed-type transport container provided on its front face with a lid is most widely used. For 12-inch semiconductor wafers, a transport container abbreviated as “FOUP” is used.
The FOUP includes a resin transport container (container main body), which is provided on its front face with a lid. Two key holes are formed in an outer face of the lid. Patent Document 1 shows an example of the structure. The carry-in and carry-out port is usually referred to as load port, which includes a stage onto which the FOUP is placed from outside. In more detail, the load port is configured to urge the stage toward a partition wall by a drive mechanism such as a motor or an air cylinder, so as to insert a key (i.e., opening/closing mechanism) into the key hole provided in the lid from the apparatus side through an opening formed in the partition wall. The key is then rotated and moved backward, so that the lid is removed.
As the semiconductor manufacturing apparatuses, various apparatuses adapted for respective processes for semiconductor manufacturing, such as a film deposition apparatus, an apparatus for forming a mask pattern, an etching apparatus, a cleaning apparatus and so on are used. Semiconductor substrates are sequentially transported among these apparatuses using the transport container. Since the number of semiconductor substrates to be processed per unit time increases more and more in recent years, the FOUP is used very frequently, and thus the failure occurrence probability of the FOUP becomes higher.
In a case of occurrence of an abnormality (failure) in the FOUP, a trouble such as falling of a component (e.g., lid) may occur. If such a trouble occurs in the load port, there is a possibility that the operation of the production line of the semiconductor manufacturing apparatuses should be stopped. It is thus desirable to detect the condition of the FOUP before the FOUP becomes abnormal.
Patent Document 1: JP2004-119427A